ITPD20120146A1 - PLANT FOR THE OPTIMIZATION OF THE EXPLOITATION OF ELECTRIC ENERGY AVAILABLE TO A BUILDING, AND PROCEDURE FOR THE USE OF SUCH SYSTEM. - Google Patents

Description

PLANT FOR THE OPTIMIZATION OF THE EXPLOITATION OF ELECTRICITY AVAILABLE TO A BUILDING, AND PROCEDURE FOR THE USE OF THIS PLANT

DESCRIPTION

The present invention relates to a plant for optimizing the exploitation of the electrical energy available to a building.

The invention also relates to a method for using this optimization system. Nowadays the need is increasingly felt, both for economic reasons and for ecological reasons, to rationalize the energy consumption of buildings, both used as homes and industrial environments, even more so in the case of buildings equipped with systems capable of exploit the so-called alternative energies, such as photovoltaic systems.

In fact, if on the one hand photovoltaic systems suffer from the unavoidable disadvantage of not producing electricity in the hours of darkness, on the other hand it is common for operators of local or national electricity grids to make two or more cost rates available to customers. electricity, establishing time slots in which energy costs more, generally during the day, and time slots in which energy costs less, usually at night.

Although the two aforementioned factors seem to complement each other, allowing users an advantageous use of the electricity produced by photovoltaics during the day and an equally convenient use of low-cost electricity from the grid in the evening and at night, the reality is often proposed in a way more complex and problematic, as in the case of managing the peak of electricity demand.

In fact, today the peak of energy demand is generally managed by decreasing the supply to the users, or alternatively interrupting the supply temporarily to some users to supply others.

Such events are, for example, extremely frequent in summer, when during the day the energy demand for the operation of the air conditioners is very high, but the network is not able to ensure the correct supply to all users, and on the other hand in the evening and night hours. , despite being electricity at a cheaper price, the demand drops drastically for natural environmental cooling.

Another typical drawback of photovoltaic systems is the management of energy production peaks by the photovoltaic system itself, for example in the event of a day of strong insolation; this energy produced by the photovoltaic system is often not exploited locally, nor can it be conveyed and delivered to the local network, thus being dissipated and unused.

The object of the present invention is to provide a plant for optimizing the exploitation of the electrical energy available to a building, capable of favoring the best possible exploitation of the available electrical energy sources, rationalizing their exploitation and reducing costs for the building or the industrial process to which it is associated.

Within the scope of this aim, an object of the invention is to provide a plant which cooperates in obviating the problems of managing local energy demand peaks.

Another object of the invention is to provide a plant that can be fitted out without particular difficulties even in existing buildings. A further object of the invention is to provide a method for using a similar plant for optimizing the exploitation of the electrical energy available to a building.

Not least object of the invention is to provide a plant for optimizing the exploitation of electrical energy available to a building, as well as a method for its use, which can be produced with known technologies.

This task, as well as these and other purposes which will appear better later, are achieved by a plant for the optimization of the exploitation of the electrical energy available to a building, comprising

- at least one alternative energy generator system, for the supply of electricity - a first insulated storage tank (13), or boiler, for the storage of domestic hot water, characterized in that it comprises

- a second tank, with high thermal inertia, for accumulation of water for the auxiliary supply of the heating / cooling system of the building environments, or of the pre-heating / pre-cooling system of an industrial process,

- a water-based heat pump, which can alternatively supply water to the heating / cooling system of a building, or to a pre-heating / pre-cooling system of an industrial process, or to supply the first tank with hot water, or to supply water hot or cold water the second tank,

- a first probe for measuring the temperature of the water in the first tank

- a second probe for measuring the water temperature in the second tank

- a third probe for measuring the temperature of the external environment

- an electronic control and management unit to rationalize the use of electricity to power the heat pump, to supply the building's electrical system and to store energy in the form of water thermally treated in said first and second tanks, according to the thermal needs of the building or the industrial processes carried out therein, to the production of electricity by at least one alternative energy plant and to the time bands of low cost of electricity from the electricity grid local.

Further characteristics and advantages of the invention will become clearer from the description of a preferred, but not exclusive, embodiment of the system according to the invention, illustrated, by way of non-limiting example, in the accompanying drawings, in which:

Figure 1 schematically represents a plant according to the invention;

Figure 2 is a block diagram relating to a method for using the plant according to the invention.

With reference to the aforementioned figures, a plant for optimizing the exploitation of electricity available to a building is indicated as a whole with the number 10.

Such plant 10 comprises

- a photovoltaic system 11 with inverter 12, for the supply of electricity,

- a first storage tank 13, or boiler, with high thermal inertia, for accumulation of domestic hot water,

- a second storage tank 14, with high thermal inertia, auxiliary, for water accumulation for the auxiliary supply of the heating / cooling system IRR of the rooms of building E, or for the supply of a pre-heating / pre-cooling system (or heating / cooling) of an industrial process,

- a water-based heat pump 15, suitable alternatively to supply water to the heating / cooling system IRR of a building E, or to a pre-heating / pre-cooling (or heating / cooling) system of an industrial process, or to supply the first storage tank 13 with hot water, for domestic hot water, or to supply the second storage tank 14 with hot or cold water, water intended for the heating / cooling system or for an industrial process plant,

- a first probe 16 for measuring the temperature of the water in the first tank 13, - a second probe 17 for measuring the temperature of the water in the second tank 14, - a third probe 18 for measuring the temperature of the external environment ,

- an electronic control and management unit 19, interconnected with the heat pump 15, with the photovoltaic system 11, with the electrical system IE of building E to which this optimization system 10 is associated, and with said probes 16, 17, 18

This electronic control and management unit 19 is adapted to rationalize the use of electrical energy for the power supply of the heat pump 15, for the supply of the electrical system IE of building E, and for the accumulation of energy in form of water thermally treated in the first 13 and second 14 storage tanks, according to the thermal needs of the building E, or to the thermal needs of the preheating / pre-cooling (or heating / cooling) system of an industrial process, to production of electricity from the photovoltaic system 11, and at any time bands of low cost of electricity from the local electricity grid RE.

The system 10 comprises a multimeter 20, or other similar and equivalent device, at the connection points between the photovoltaic system 11 and the RE electrical network, to check whether the photovoltaic system 11 is giving power to the RE electrical network or if the building E is absorbing energy from the electricity grid RE, that is, if the power absorbed by the optimization plant 10 itself comes from the electricity grid.

The system components connected to said electronic control and management unit 19 communicate by means of the Modbus RTU protocol, or by means of another similar and equivalent protocol.

The system 10 according to the invention can also comprise a secondary multimeter, or other equivalent device, not illustrated for simplicity, to be connected to the inverter 12, in the event that the inverter 12 itself is unable to communicate with the Modbus RTU protocol or other similar protocol.

An additional dedicated multimeter, or other equivalent device, is also set up if you want to keep the power absorbed by a single load under control, for example the heat pump 15.

A similar system 10 according to the invention is capable of combining the production of electrical energy from a photovoltaic system 11 with the production of thermal and cooling energy of the heat pump 15, using the first storage tanks 13 and second 14 to use more the heat pump 15 is continuous and efficient, reducing the continuous switch-on and switch-off steps.

In fact, the electronic control unit 19 is programmed to operate the heat pump 15 whenever there is the possibility of accumulating thermal energy in the tanks 13 and 14 in the form of heat-treated, or heated or cooled water, giving priority to the operation of the pump. heat 15 in the most economically advantageous periods of electricity supply.

Then the electronic unit 19 is programmed to operate the heat pump 15

- or when there is a part of power produced by the photovoltaic system 11 which is in excess of the power supplied to the electrical system IE of building E, and which therefore can be destined for the heat pump 15 instead of being supplied to the electrical network RE a to which the photovoltaic system 11 is connected,

- or in the case of overproduction of energy by the photovoltaic system 11, on particularly sunny days,

- or in a time slot with a reduced cost of energy from the RE electricity grid, if power is not available from the photovoltaic system 11, such as at night.

Both the sanitary water in the first tank 13 and the conditioning water in the second tank 14 are brought and maintained at temperature by using the heat pump 15 at the most energetically convenient moments of the day.

The accumulations of the tanks 13 and 14 are then used in the respective systems of building E, or the DHW circuit CS, or the heating / cooling system IRR, in the moments in which the electricity from the network, if absorbed, it would be more expensive, and at which times, therefore, the electronic control unit 19 is programmed to operate the heat pump 15 as little as possible.

The system 10 is therefore able to manage the accumulations, sized in such a way as to have a suitable autonomy, for example of a few days, favoring the operation of the heat pump in the hours typically of good insolation or in the time bands with low cost of electric energy .

The possibility of accumulating energy in the form of hot or cold water, in addition to increasing and controlling the self-consumption by building E, or by the industrial process, of the electricity produced by the photovoltaic system 11, also solves the problem of the peak energy demand at local level, since in the event of a poor supply from the RE electricity network, the tanks 13 and 14 are always able to ensure the regular operation of the DHW circuit CS and the heating system / IRR cooling, after appropriate sizing of the same tanks 13 and 14.

System 10 is therefore designed to supply the minimum possible electrical power to the RE electrical network, preferring the self-consumption of energy by building E.

The invention also relates to a process, or method, for the use of a plant 10 for optimizing the exploitation of the electrical energy available to a building, as described above.

This procedure, schematized in figure 2, includes the following operations:

- set the following temperature values for the heat pump 15 in the electronic control unit 19:

- ideal Tac hot water temperature ± d accumulated in the second tank 14 for air conditioning - Tac min minimum temperature accumulated hot water for air conditioning in the second tank 14

- maximum temperature Tacmax hot water storage for conditioning in the second tank 14 - ideal temperature Tafid cold water stored in the second tank 14 for conditioning - minimum temperature Tafmin cold water storage for conditioning in the second tank 14 - maximum temperature Tafmax cold water storage for conditioning in the second tank 14 - ideal domestic hot water storage temperature Tb ± din said first tank 13

- minimum domestic hot water storage temperature Tbmin in the first tank 13

- maximum domestic hot water storage temperature Tbmax in the first tank 13,

- set the time bands for electricity supply from the RE electricity network at a lower rate - establish the operating mode for the heat pump 15, 'summer' mode for the production of cold water or 'winter' mode for the production of hot water ,

- detect the ambient temperature Te,

- measure the temperature Tb of the water in the first tank 13 for domestic hot water

detect the temperature Ta of the water in the second tank 14 for water for the heating / cooling system

- detect the power produced by the Ptot.iFv photovoltaic system,

- check if the IE electrical system is absorbing Ρass.ΙΕ power from the RE electrical network, or if the photovoltaic system 11 is supplying power to the IE electrical system and to the electrical network

RE, i.e. if a Pecc part of the Ptot.iFv power produced by the photovoltaic system 11 exceeds the absorbed power Pass.iE by the electrical system IE of building E,

- if the IE electrical system is absorbing power from the electrical network Ρass.ΙΕ check if compared to the contractual absorbable power Pass.cont there is a part of Pass.pc power available sufficient to power the heat pump 15,

- if the part of excess power available Pece is sufficient to power said heat pump 15, if it is found to be in a time band of high cost, and if one of the temperatures Ta, Tb detected in the first 13 and second 14 tanks is lower at the corresponding minimum temperature Tacmin, Tbmin, or higher than the maximum temperature Tafmax if the heat pump 15 is in 'summer' mode and the second tank 14 stores cold water, then start the heat pump 15 to bring or said first tank 13 at the corresponding minimum temperature Tbmin, or said second tank 14 at minimum Tacmin temperature, in winter mode, or maximum Tafmax in summer mode,

- if a pitch part of the power produced by the photovoltaic system Ptot.iFv exceeds the power absorbed Pass.iE by the electrical system IE of building E, and if this excess power is sufficient to power said heat pump 15, then the heat pump is fed to bring either the water in said first tank to its ideal temperature Tbid, or the water in said second tank to the maximum temperature Tacmax or minimum Tafmin, depending on whether the mode of use of the heat 15 either 'winter' or 'summer'.

This method according to the invention further provides that

if said part of available power PassPC is sufficient to power said heat pump 15, if it is found to be in a time band of reduced cost, and if one of the temperatures Ta, Tb detected in the first 13 and second 14 tanks is lower than the corresponding ideal temperature Tacid, Tbid, or higher than the ideal Tafid temperature if the heat pump 15 is in 'summer' mode and the second tank 14 is storing cold water,

- then starting the heat pump 15 to bring either said first tank 13 to the corresponding ideal temperature Tbid, or said second tank 14 to the ideal Tacid or Tafid temperature.

The method according to the invention further provides that

- if there is a Pecc part of the power produced by the photovoltaic system PtotlFV which is in excess of the absorbed power PassIE and sufficient to power said heat pump 15, the power supply of said heat pump to bring either the water into said first tank at its ideal temperature Tbid, or the water in said second tank at maximum Tacmax or minimum Tafmin temperature, occurs in successive cycles, designed to raise the temperature by a predetermined Itemp temperature range, for example by 2 ° C, up to reaching the preset temperatures Tacmax, Tafmin or Tbid.

During each cycle, at pre-established ITC time intervals, it is checked whether there is a Pecc part of the power produced by the PtotlFP photovoltaic system which is in excess of the absorbed power PassIE and sufficient to power said heat pump 15, or if the power supply of the heat pump comes from the RE electrical network, and no longer from the photovoltaic system.

In Figure 2 the block diagram 100 schematically represents the series of operations described above.

The first block 101 represents the assumption by the electronic control unit 19 of the temperature data, with setting of the current date, and of the dates for the passage from summer to winter mode for the heat pump 15.

If necessary, the change of mode from summer to winter and vice versa can be carried out manually, so as to be able to apply the system and procedure even to the simple heating, or pre-heating / cooling, or pre-cooling, of an industrial process.

Blocks 102 and 103 indicate respectively the loading, by the electronic control unit 19, of the Tacid, Tafid and Tbid temperatures, depending on the ambient temperature Te and on the basis of predefined and corresponding temperature curves or the summer operating mode or to the winter operating mode of the heat pump 15.

Block 104 establishes the automatic start or non-start of the sequence of operations described above.

In the event of automatic start-up, block 105 schematically checks whether the IE electrical system is absorbing power from the Pass.IE electrical network and whether compared to the contractual absorbable power

Pass.cont there is enough power available to power the heat pump

Pass.PC.

If so, i.e. the electrical system IE is absorbing energy from the RE network, and therefore is using expensive electricity, and there is power available for the heat pump, then the heat pump 15 is activated only to maintain temperatures Ta and Tb in the first and second tanks at the minimum values Tacmin, Tbmin, or maximum Tafmax in the case of summer mode, resulting in the lowest possible use of expensive electricity from the RE network.

In the negative case, i.e. there is no power available to feed the heat pump 15, then, block 108, it is evaluated whether Tac, Taf or Tb are lower, or higher in the case of Taf, than the respective Tacmin, Tafmax, Tbmin.

If yes, go to blocks 106 and 107, if not, go to block 109, according to which the control unit 19 checks whether the photovoltaic system 11 is transferring current to the grid RE or not.

If not, that is, if the photovoltaic system is not yielding power to the grid, and therefore the heat pump 15 needs the energy of the RE grid to function, the control unit 19 evaluates, block 110, if it is in correspondence a low-cost time slot for electricity from the RE network.

If yes, block 111, the heat pump 15 is set to operate until the temperatures Ta and Tb are brought to the ideal values, thus operating advantageously in the time of reduced energy cost.

If not, the control unit 19 returns to the operation of block 108.

If, on the other hand, it checks it in block 109, whether the photovoltaic system 11 is yielding current to the RE network or not, it has an affirmative answer, i.e. an excess power is available Pecc useful to power the heat pump 15 by exploiting the energy produced by the system photovoltaic 11 which is not absorbed by the electrical system IE of building E, then from block 110, the series of cycles 112 starts to bring the temperature Ta to its minimum values in summer and maximum in winter, and Tb to its value ideal.

Block 113 schematises the periodic check that the photovoltaic system 11 is always giving power to the grid RE.

If there is no more power transferred to the network, then we return to blocks 106 and 107, according to which the heat pump 15 draws current from the network RE and is therefore operated only to keep Ta and Tb at the minimum values below which the plants served would give a disservice.

The electronic control unit 19 can be easily managed by means of an operator panel, for example of the Touch Screen type, which collects all the data, and through the PLC logic supplied with the unit 19 processes all the information according to the procedure and algorithm described above.

The operator panel also displays the data of the photovoltaic system 11, the load balance, the alarms of the same photovoltaic system 11 and the alarms of the heat pump 15.

From the control panel it is also possible to set all the sensitive parameters of the system 10 as required by the algorithm.

Should there be the need to integrate the system with a remote supervision and telecontrol system, various solutions are available depending on availability and objectives: it is possible to view only in the local network, or through a router it is possible to read all the data from the operator panel and host a graphic web page that can be viewed remotely, for example by using a suitable data SIM and relative hardware to be able to view the data on a PC connected to the internet or via smartphone.

The system 10 can be equipped with a UPS, an uninterruptible power supply, in order to guarantee a minimum of control service even in the event of short interruptions in the power supply. In practice it has been found that the invention achieves the intended aim and objects.

In particular, the invention has developed a plant for the optimization of the exploitation of the electricity available to a building, capable of favoring the best possible exploitation of the available electrical energy sources, rationalizing their exploitation and decreasing the costs for the building. Therefore, with the invention, a plant has been developed which cooperates in obviating the problems of managing local energy demand peaks, as well as cooperating in solving the problems of peak production of energy by the photovoltaic plant.

In addition, the invention has developed a system that can be set up without particular difficulties even in existing buildings.

Last but not least, the invention provides a plant for optimizing the exploitation of the electrical energy available to a building, as well as a method for its use, which can be produced with known technologies.

The invention thus conceived is susceptible of numerous modifications and variations, all of which are within the scope of the inventive concept; moreover, all the details can be replaced by other technically equivalent elements.

In practice, the materials used, as well as the contingent shapes and dimensions, may be any according to requirements and to the state of the art.

Where the features and techniques mentioned in any claim are followed by reference marks, these marks have been affixed for the sole purpose of increasing the intelligibility of the claims and consequently such reference marks have no limiting effect on the interpretation of each element. identified by way of example by these reference signs.

Claims (2)

CLAIMS 1) Plant (10) for the optimization of the exploitation of the electrical energy available to a building, comprising - at least one alternative energy generator system, for the supply of electricity - a first insulated storage tank (13), or boiler, for the storage of domestic hot water, characterized by the fact that it comprises - a second insulated storage tank (14), auxiliary, for water accumulation for the auxiliary supply of the heating / cooling system (IRR) of the rooms of the building (E), or of a heating or preheating system / cooling or pre-cooling of an industrial process, - a water-based heat pump (15), which can alternatively supply water to the heating / cooling system (IRR) of a building, or to a pre-heating / pre-cooling system of an industrial process, or to supply hot water to the first tank (13), or to supply the second tank (14) with hot or cold water, - a first probe (16) for measuring the temperature of the water in the first tank (13) - a second probe (17) for measuring the water temperature in the second tank (14) - a third probe (18) for measuring the temperature of the external environment - an electronic control and management unit (19) to rationalize the use of electricity to power the heat pump (15), to supply the electrical system (IE) of the building (E) and to the accumulation of energy in the form of thermally treated water in said first (13) and second (14) tanks, based on the thermal requirements of the building (E) or of the industrial processes carried out therein, for the production of electricity of at least one alternative energy generating plant, and to any time bands of low cost of electricity from the local electricity grid (RE). 2) Plant according to claim 1, which is characterized by the fact that said at least one alternative energy generating plant is given by a photovoltaic plant (11) with inverter (12). 3) System according to the preceding claims, characterized by the fact that it comprises a multimeter (20), or other similar and equivalent device, at the connection points between the photovoltaic system and the electricity grid to check whether the photovoltaic system is giving up power to the electricity grid or if the building (E) is absorbing energy from the electricity grid (RE), or if the power absorbed by the optimization plant (10) itself comes from the electricity grid. 4) Plant according to the preceding claims, which is characterized by the fact that the components of the plant connected to said electronic control and management unit (19) communicate by means of Modbus RTU protocol, or other similar and equivalent protocol. 5) Process for the use of a plant for the optimization of the exploitation of the electrical energy available to a building, according to one or more of the preceding claims, characterized in that it comprises the following operations: - set the following temperature values for the heat pump (15) in the electronic control unit (19) - ideal hot water temperature (Tacid) accumulated in the second tank (14) for conditioning - minimum temperature (TaCmin) hot water storage for conditioning in the second tank - maximum temperature (Tacmx) hot water storage for conditioning in the second tank - ideal cold water temperature (Tafid) accumulated in the second tank for conditioning - minimum temperature (Tafmin) cold water storage for conditioning in the second tank - maximum temperature (Tafmax) cold water storage for conditioning in the second tank - ideal domestic hot water storage temperature (Tbid) in said first tank (13) - minimum domestic hot water storage temperature (Tbmin) in the first tank (13) - maximum domestic hot water storage temperature (Tbmax) in the first tank, - set the time bands for electricity supply from the electricity network (RE) at a lower rate - set the operating mode for the heat pump (15), summer mode for the production of cold water or winter mode for the production of hot water , - measure the ambient temperature (Te), - measure the water temperature (Tb) in the first tank (13) for domestic hot water - measure the water temperature (Ta) in the second water tank for the heating / cooling system - detect the power produced by the photovoltaic system (PtotlFV), - check if the electrical system (IE) is absorbing power (PassIE) from the electricity grid (RE), or if a part (Pecc) of the power produced by the photovoltaic system (PtotlFV) is in excess of the power absorbed (PassIE) by the '' electrical system of the building, - if the electrical system (IE) is absorbing power from the electrical network (PassIE), check whether compared to the contractual absorbable power (Pass.cont) there is sufficient power available to power the heat pump (PassPC) - if the available power part (PassPC) is sufficient to power said heat pump (15), if it is found to be in a time band of high cost, and if one of the temperatures (Ta, Tb) detected in the first tanks ( 13) and second (14) is lower than the corresponding minimum temperature (Tacmin, Tbmin), or higher than the maximum temperature (Tafmax) if the heat pump (15) is in 'summer' mode and the second tank (14 ) accumulate cold water, then start the heat pump to bring either said first tank to the corresponding minimum temperature, or said second tank to the minimum temperature, in winter mode, or maximum in summer mode, - if a part (Pecc) of the power produced by the photovoltaic system (PtotlFV) exceeds the power absorbed (PassIE) by the electrical system of the building, and if this excess power (Pecc) is sufficient to power said heat pump (15), then the heat pump is fed to bring either the water in said first tank to its ideal temperature (Tbid), or the water in said second tank at the maximum (Tacmax) or minimum (Tafmin) temperature, to depending on whether the mode of use is winter or summer. 6) Process according to the preceding claim, which is characterized in that - if said part of available power (PassPC) is sufficient to power said heat pump (15), if it is found to be in a time band of reduced cost, and if one of the temperatures (Ta, Tb) detected in the first (13) and second (14) tanks is lower than the corresponding ideal temperature (Tacid, Tbid), or higher than the ideal temperature (Tafid) if the heat pump (15) both in 'summer' mode and the second tank (14) stores cold water, then start the heat pump to bring either said first tank to the corresponding ideal temperature, or said second tank to the ideal temperature. 7) Process according to the preceding claims, which is characterized by the fact that - if there is a part (Pecc) of the power produced by the photovoltaic system (PtotlFP) which is in excess of the absorbed power (PassIE) and sufficient to power said pump (15), the supply of said heat pump to bring either the water in said first tank to its ideal temperature (Tbid), or the water in said second tank at the maximum (Tacmax) or minimum (Tafmin) temperature ), takes place in successive cycles, designed to raise the temperature by a predetermined temperature interval (Itemp) up to the raqqiunqiment or the preset temperatures Tacmax, Tafmin or Tbid. 8) Process according to the preceding claim, which is characterized by the fact that during each cycle, at predetermined time intervals (ITC), it is checked whether there is a part (Pecc) of the power produced by the photovoltaic system (PtotlFP) which is exceeding the absorbed power (PassIE) and sufficient to power said heat pump (15), or if the heat pump power supply comes from the electrical network (RE), and no longer from the photovoltaic system.